i.mx287学习笔记4-使用QT控制LED

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目录

1.安装QT CREATOR

2.硬件连接

3.驱动源码

4.编译驱动/测试驱动

5.创建QT界面

6.编译QT

7.运行

8.源码

1.安装QT CREATOR

sudo apt-get install qt5-default qtcreator

2.硬件连接

照片看不太清，对照丝印和原理图，LED连接在GPIO3 PIN26上

在内核源码里面引脚定义是PINID_SAIF1_SDATA0

3.驱动源码

驱动是官方例程，直接改个IO口就行

/*
   GPIO Driver driver for EasyARM-iMX283
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/ioctl.h>
#include <linux/delay.h>
#include <linux/bcd.h>
#include <linux/capability.h>
#include <linux/rtc.h>
#include <linux/cdev.h>
#include <linux/miscdevice.h>
#include <linux/gpio.h>

#include <../arch/arm/mach-mx28/mx28_pins.h>

#define DEVICE_NAME	"imx28x_oled"

#define LED_GPIO	MXS_PIN_TO_GPIO(PINID_SAIF1_SDATA0)		//for 283 287A/B

/*--------------------------------------------------------------------------------------------------------
*/
static int gpio_open(struct inode *inode, struct file *filp);
static int  gpio_release(struct inode *inode, struct file *filp);
ssize_t gpio_write(struct file *filp, const char __user *buf, size_t count,
                loff_t *f_pos);
static int gpio_ioctl(struct inode *inode,struct file *flip,unsigned int command,unsigned long arg);
static int gpio_init(void);
static void gpio_exit(void);

/*--------------------------------------------------------------------------------------------------------
*/

static int gpio_open(struct inode *inode, struct file *filp)
{
	gpio_request(LED_GPIO, "led");

	return 0;
}

static int  gpio_release(struct inode *inode, struct file *filp)
{
	gpio_free(LED_GPIO);
	return 0;
}


ssize_t gpio_write(struct file *filp, const char __user *buf, size_t count,
                loff_t *f_pos)
{
	char data[2];

	copy_from_user(data, buf, count);
	gpio_direction_output(LED_GPIO, data[0]);

	return count;
}

static int gpio_ioctl(struct inode *inode,struct file *flip,unsigned int command,unsigned long arg)
{
	int data;
	
	switch (command) {
	case 0: 
		gpio_direction_output(LED_GPIO, 0);
		break;
	
	case 1:
		gpio_direction_output(LED_GPIO, 1);
		break;
	}

	return 0;
}

static struct file_operations gpio_fops={
	.owner		= THIS_MODULE,
	.open 		= gpio_open,
	.write		= gpio_write,
	.release	= gpio_release,
	.ioctl		= gpio_ioctl,
};

static struct miscdevice gpio_miscdev = {
	.minor  = MISC_DYNAMIC_MINOR,
	.name	= DEVICE_NAME,
	.fops	= &gpio_fops,
};	

static int __init gpio_init(void)
{

	misc_register(&gpio_miscdev);
	printk(DEVICE_NAME" up. \n"); 

	return 0;
}

static void __exit gpio_exit(void)
{
	misc_deregister(&gpio_miscdev);
	printk(DEVICE_NAME " down.\n");
}

module_init(gpio_init);
module_exit(gpio_exit);

MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("jun");
MODULE_DESCRIPTION("GPIO DRIVER FOR EasyARM-i.MX28xx");

4.编译驱动/测试驱动

测试代码

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <errno.h>
#include <limits.h>
#include <asm/ioctls.h>
#include <time.h>
#include <pthread.h>


int main(void)
{
	int fd;
	char buf[1] = {0};

	fd = open("/dev/imx28x_led", O_RDWR);
	if (fd < 0) {
		perror("open /dev/imx283_led");
	}

	printf("test write....\n");
	buf[0] = 0;
	write(fd, buf, 1);
	sleep(2);

	buf[0] = 1;
	write(fd, buf, 1);
	sleep(1);	

	printf("test ioctl..... \n");
	ioctl(fd, 0);
	sleep(2);
	ioctl(fd, 1);
}

编译测试代码

将代码拷贝到设备

可以看到设备上LED在翻转

5.创建QT界面

三个按键，每个按键实现一个功能

void MainWindow::on_pushButton_clicked()
{
    QProcess *process = new QProcess();
    process->start("sh led_insmod.sh");
}

void MainWindow::on_pushButton_2_clicked()
{
    QProcess *process = new QProcess();
    process->start("sh led_rmmod.sh");
}

void MainWindow::on_pushButton_3_clicked()
{
    QProcess *process = new QProcess();
    process->start("./led_test");
}

这里我创建了两个shell，其实没这么麻烦，直接输入命令就行，这里是为了测试qt调用shell

6.编译QT

下载到设备

7.运行

点击按键，实现驱动加载,运行，卸载

8.源码

https://download.csdn.net/download/jun626/11572105